BACKGROUND OF THE INVENTION
[0001] The present disclosure relates generally to a lyophilization system and associated
method and, in particular, to a system and method for freeze-drying heat-sensitive
substances such as biological materials or pharmaceutical formulations under aseptic
or contaminant-reduced conditions.
[0002] Dry storage can increase the shelf life and convenience of heat-sensitive substances
such as, but not limited to, biological materials, pharmaceutical formulations, and
therapeutic products including chemical compositions, plasma-derived therapies, and
recombinants. Such products can be unstable in solution and require lyophilization,
particularly when produced as parenterals. Lyophilization is a process for drying
heat-sensitive substances by freezing the substances and then subliming the ice or
other frozen solvent in a high vacuum.
[0003] It is often necessary to keep heat-sensitive substances sterile and free from microorganisms
and other contaminants to avoid decomposition or degradation, and prevent possible
infection when the material is introduced into a patient. Heat-sensitive substances
can be exposed to contaminants during transportation to and from a freeze-dryer (lyophilizer).
As a result, the freeze-drying operating area undergoes sterilization to minimize
exposure of the material to contaminants. This effectively increases the labor and
costs associated with lyophilization and sterilization.
[0004] Many freeze-drying processes involve placing open, or partially stoppered, containers
of heat-sensitive substances in a freeze-dryer, such that the containers are exposed
to the environment until the freeze-drying process is complete, to allow a path for
solvent vapor to be removed from the material. This practice exposes the heat-sensitive
material to potential contamination during freeze-drying. To minimize potential contamination,
freeze-drying equipment can be sterilized via steam or chemicals before loading each
new batch of material to be lyophilized. This too increases labor and costs associated
with lyophilization and sterilization.
[0005] Additionally, some freeze-drying systems and methods require lyophilized materials
to be repackaged and/or re-handled, such as by capping or crimping. This repackaging
presents another opportunity to introduce contaminants and increase costs.
[0006] The present disclosure addresses the need for a system and method that prevent, or
at least reduce, contamination of heat-sensitive substances, such as biological or
pharmaceutical material, during filling, freeze-drying, packaging, storage, and use.
SUMMARY OF THE INVENTION
[0007] Briefly, and in general terms, the present disclosure is directed towards a system
that includes an upright, vertical container and at least one integrated gas-permeable
membrane that transmits air or solvent vapor out of the container while preventing
entry of contaminants. A method can include filling a vertical container with a heat-sensitive
substance, inserting a membrane into the body or cap of the container such that the
membrane covers the heat-sensitive substance, and freeze-drying the container to produce
a lyophilized material.
[0008] Embodiments of the disclosure include a system comprising an upright container comprising
a body defined by an upper portion, with an opening formed therein, and a lower portion.
A removable cap can be sealably attached to the upper portion of the body and configured
to cover the opening. A membrane can be configured to transmit air or solvent vapor
out of the upright container while resisting liquid or contaminant passage into the
upright container, where the membrane is disposed above a fill line of the upright
container. The system can include a membrane frame coupled to the perimeter of the
membrane. The membrane frame can attach to the upper portion of the body such that
the membrane covers the opening of the upright container. The membrane frame can attach
to the top of the body via a lip and groove mechanism or threads. The membrane frame
can be inserted into the upper portion of the body or the cap via friction fit, a
lip and groove mechanism, or threads. The membrane frame is inserted into the cap
of the upright container. The upright container can be a glass lyophilization vial,
a conical centrifuge tube, a microcentrifuge tube, or a blood collection tube. The
cap can be a screw cap, a snap cap closure, a plug, or a stopper. The system can comprise
a heat-sensitive substance. The heat-sensitive substance can be a biological material,
a pharmaceutical formulation or a therapeutic product.
[0009] Embodiments of the disclosure include a method for freeze-drying a heat-sensitive
substance. The method comprises filling a vertical container with the heat-sensitive
substance, incorporating a membrane into the vertical container, and lyophilizing
the heat-sensitive substance to produce a freeze-dried material, wherein air or solvent
vapor is removed from the vertical container through the membrane. The method can
comprise using the membrane to prevent contaminants from entering the vertical container
during lyophilization. The method can comprise storing the freeze-dried material in
the vertical container. The method can comprise reconstituting the freeze-dried material
in a solvent to produce a reconstituted product. The reconstituted product can be
administered to a human or animal subject via infusion or via injection. The freeze-dried
material can be reconstituted by piercing the membrane with a syringe carrying the
solvent and dispensing the solvent into the vertical container.
[0010] Other features and advantages of the present disclosure will become apparent from
the following detailed description, taken in conjunction with the accompanying drawings,
which illustrate, by way of example, the principles of the disclosure.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011]
FIG. 1 is a top view of an embodiment of a membrane;
FIG. 2 is a top view of another embodiment of a membrane;
FIG. 3 is a perspective, side view of an embodiment of a vertical container;
FIG. 4 is a perspective, side view of another embodiment of a vertical container;
FIG. 5 is a perspective, side view of yet another embodiment of a vertical container;
FIG. 6A is a partially transparent, side view of a vertical container with a membrane
integrated into the lid of the container according to an embodiment of the disclosure;
FIG. 6B is a top view of the vertical container and membrane of FIG. 6A;
FIG. 6C is a partially transparent, side view of the lid of FIG. 6A with a cover sealing
the membrane;
FIG. 7A is a side view of a vertical container with a membrane inserted in the upper
portion of the container body according to an embodiment of the disclosure;
FIG. 7B is a top view of the vertical container and membrane of FIG. 7A;
FIG. 8A is a side view of a vertical container with a membrane disposed over the opening
of the container body according to an embodiment of the disclosure;
FIG. 8B is a top view of the vertical container and membrane of FIG. 8A;
FIG. 9A is an exploded, perspective view of a vertical container with a collar according
to an embodiment of the disclosure;
FIG. 9B is a perspective, side view of the vertical container of FIG. 9A;
FIG. 10 is a front view of a flexible, vertical container with a membrane according
to an embodiment of the disclosure; and
FIG. 11 is a flowchart of a method for freeze-drying a heat-sensitive substance in
a vertical container with a membrane according to an embodiment of the disclosure.
DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS
[0012] For the following defined terms, certain definitions shall be applied, unless a different
definition is given elsewhere in this patent document.
[0013] The terms "a," "an," and "the" are used to include one or more than one, independent
of any other instances or usages of "at least one" or "one or more."
[0014] The term "or" is used to refer to a nonexclusive or, such that "A or B" includes
"A but not B," "B but not A," and "A and B."
[0015] All numeric values are assumed to be modified by the term "about," whether or not
explicitly indicated. The term "about" generally refers to a range of numbers that
one of skill in the art would consider equivalent to the recited value (e.g., having
the same function or result). In many instances, the term "about" can include numbers
that are rounded to the nearest significant figure.
[0016] The recitation of numerical ranges by endpoints includes all numbers and sub-ranges
within that range (e.g., 1 to 4 includes 1, 1.5, 1.75, 2, 2.3, 2.6, 2.9, etc. and
1 to 1.5, 1 to 2, 1 to 3, 2 to 3.5, 2 to 4, 3 to 4, 3 to 4.25, etc.).
[0017] The term "patient" is intended to include mammals such as for human or veterinary
applications.
[0018] The term "upright" refers to an object having its main axis or a main part vertically
oriented when in an operating condition or use position.
[0019] Turning now to the figures, which are provided by way of example and not limitation,
the present disclosure is directed to a system and method for freeze-drying a heat-sensitive
substance in a vertical container with a membrane for transmitting air or vapor solvent
out of the container.
[0020] FIGS. 1 and 2 illustrate embodiments of membranes that can be integrated into a container
for housing a heat-sensitive material that undergoes a freeze-drying process. Membranes
102 and 112 can be selectively permeable, allowing air or solvent vapor to escape
the container during lyophilization while preventing, or at least reducing, entry
of liquid and/or contaminants into the container. Membranes 102 and 112 can be made
of suitable materials with aseptic barrier properties, high resistance to penetration
by moisture or liquids such as water, and low resistance to solvent vapor flow. Such
materials can include, but are not limited to, aseptic papers, wove or non-woven polymeric
fabrics such as spun-bonded polyolefin, porous polymer membranes such as polytetrafluoroethylene
(PTFE) or expanded PTFE, glass fiber, nitrocellulose, mixed cellulose, esters, polyvinylidene
fluoride (PVDF), polyethersulfone, polycarbonate, nylon, polypropylene, polyvinyl
chloride (PVC), or combinations thereof. In some preferred embodiments, membranes
are made of PTFE due to its hydrophobicity and solvent vapor flow for a nominal pore
size. While membranes 102 and 112 are circular, it will be understood that the shape
of the membrane can be selected to accommodate the shape of a particular container.
[0021] As shown in FIG. 1, membrane assembly 100 includes membrane 102 and frame 104 coupled
to the perimeter of the membrane. In some embodiments, membrane assembly 100 can be
inserted into the neck or upper portion of a container body. In some embodiments,
membrane assembly 100 can be inserted or integrated into the cap, lid, plug, or stopper
of the container. In some embodiments, membrane assembly 100 can be secured to the
opening of the container body. The membrane assembly 100 can be inserted into the
body or cap of the container via friction fit, a lip and groove mechanism for snapping
in, mating threads for screwing in, or other suitable mechanisms. The membrane assembly
100 faces up when the container body is in the upright position.
[0022] In alternative embodiments, such as illustrated in FIG. 2, membrane 112 includes
fastening band 114 coupled to the perimeter of the membrane. The underside of the
fastening band can contain an adhesive to secure membrane 112 over the opening of
a container body.
[0023] Membranes can be integrated into variously sized and shaped upright containers including,
but not limited to, cosmetic bottles, lyophilization bottles or vials, conical centrifuge
tubes, microcentrifuge tubes, vacutainers, blood collection tubes, round bottom centrifuge
tubes, test tubes, and/or pouches. Containers can be made from rigid material such
as various plastic or glass or from a flexible material. Containers can be self-standing
or used in conjunction with a tray or holder. Containers can be transparent and allow
for inspection of the heat-sensitive substance prior to, during, and after lyophilization.
[0024] Membranes can be incorporated into the container body or cap. Such caps can include,
but are not limited to, screw caps, flange plug caps, plug closures, flange cap closures,
threaded caps, snap cap closures, hinge caps, and/or stoppers. Caps can be coupled
to the body of the container via a hinge or entirely removable. Membranes are oriented
such that the transfer of air or solvent vapor out of the container is generally in
the vertical direction. That is, the membrane is positioned such that its major surface
area is oriented horizontally (i.e., one side of the membrane faces up when the container
body is in the upright position).
[0025] FIGS. 3-5 illustrate examples of upright containers 120, 130, and 140 that can be
used with membranes 102 and/or 112 in a freeze-drying process. Heat-sensitive substances
to be freeze-dried can be deposited into the containers prior to lyophilization.
[0026] FIGS. 6A, 6B, 6C, 7A, 7B, 8A, and 8B illustrate various integration points (indicated
by dashed lines) for a membrane in an upright container. During lyophilization, solvent
vapor passes through the membrane and exits the container (indicated by solid arrows),
while particulate of the heat-sensitive substance is retained in the container and
contaminants are excluded.
[0027] As shown in FIGS. 6A, 6B and 6C, container 150 includes body 154 and cap 152. Frame
158 (shown in FIG. 6B) of membrane 156 can be inserted into cap 152. Prior to capping,
the interior of body 154 is filled with heat-sensitive substance 160 which subsequently
undergoes freeze-drying.
[0028] Container 150 can optionally include removable cover or insert 162 configured to
seal cap 152 after lyophilization.
[0029] As shown in FIGS. 7A and 7B, container 200 includes body 204 and cap 202. Frame 208
(shown in FIG. 7B) of membrane 206 can be inserted into the upper portion of body
204 below opening 210 and above fill line 212 of heat-sensitive substance 214. Frame
208 can be inserted via friction fit, snapping in, or screwing on. Prior to insertion
of membrane 206, the interior of body 204 is filled with heat-sensitive substance
214 which subsequently undergoes freeze-drying. In some embodiments, after lyophilization,
body 204 can be sealed with cap 202.
[0030] FIGS. 8A and 8B illustrate container 250 that includes body 254 and cap 252. Membrane
256 can be snapped or screwed onto the top of body 254 such that the membrane covers
opening 258. In some embodiments, membrane 256 can be secured over opening 258 via
an adhesive band (not shown). Prior to attachment of membrane 256 to opening 258,
the interior of body 254 is filled with heat-sensitive substance 260. In some embodiments,
after lyophilization, body 254 can be sealed with cap 252.
[0031] FIGS. 9A and 9B illustrate another embodiment of a vertical container that can be
used with a membrane. Container 300 includes lid 302 and body 304 with removable collar
306 disposed therebetween. In these embodiments, a membrane can be inserted into collar
306. Following lyophilization of a heat-sensitive substance, the container can be
sealed with lid 302.
[0032] FIG. 10 illustrates an embodiment of a flexible container that can house a heat-sensitive
substance for freeze-drying. Flexible container 350 includes front side or wall 352
having a membrane disposed in upper portion 3 52a and a back side or wall (not shown).
Flexible container 350 can be held in an upright position, such that the membrane
faces outward, by a tray or holder (not shown) to support the front and back walls.
Flexible container 350 can be made of suitable, sealable materials including, but
not limited to, medical grade plastic such as PCV, polypropylene, or high density
polypropylene.
[0033] Membrane 354 disposed in upper portion 352a vents air or solvent vapor out of flexible
container 350 during freeze-drying and prevents, or at least reduces, liquid and/or
contaminant passage into the container. Membrane frame 356 is coupled to the perimeter
of and provides support to the membrane. Membrane frame 356 can mate with receiving
frame 358 extending through front side 352 of the container, thereby attaching the
membrane to the container. In some embodiments, container 350 includes more than one
membrane. For example, the container could include a membrane on the front and back
walls.
[0034] Flexible container 350 includes at least one material entry port 360 for receiving
a heat-sensitive substance, with or without the presence of additives, modifiers,
or preservatives, into the interior of the container. Entry port 360 can be positioned
below membrane 354 so as to prevent the membrane from collecting moisture or becoming
wet when the heat-sensitive substance is introduced into the container. Flexible container
350 can also include reconstitution port 362 and/or application port 364 extending
through the lower portion of the container. Ports 362 and 364 allow for aseptic introduction
of a reconstitution solution, such as water or saline, and subsequent administration
of the reconstituted product to a patient.
[0035] In particular embodiments, flexible container 350 is used to receive, freeze-dry,
store, reconstitute, and administer biological materials such as blood plasma. In
these embodiments, flexible container 350 functions as a blood plasma unit, including
approximately 250-270 mL of blood plasma from a single donor or pooled donors. The
blood plasma unit can be dried such that its moisture content is below 5% by weight.
[0036] Once the heat-sensitive material is lyophilized in any of the vertical containers
disclosed herein, the container can be sealed and/or stored at conditions (temperature,
humidity, light exposure, etc.) appropriate for the freeze-dried material. In certain
embodiments, the cap and/or membrane can be removed (e.g., cut off) and the flexible
container sealed at or below the former location of the cap and/or membrane. Lyophilized
containers can be bar coded and tagged with appropriate identifying information, storage
conditions, and/or reconstitution and administration instructions. The bar coding
and tagging can, for example, reflect biological material identification, including
blood plasma source, blood type, date of collection, etc. To keep track of such information,
the bar code printed on the identification tag can be scanned and labels with associated
information can be printed. The printed labels can be placed on an external foil containment
pouch and a final packaging, for example. The lyophilized material can then be reconstituted
with an appropriate solvent and used. In some embodiments, use includes administering
the reconstituted material to a human or animal patient.
[0037] FIG. 11 illustrates a method for freeze-drying and reconstituting a heat-sensitive
substance using a container disclosed herein. Container & Membrane Selection Stage
410 of Method 400 includes selecting a container and accompanying permeable membrane
for a particular heat-sensitive substance. Factors that can influence container and
membrane selection include, but are not limited to:
- chemical and physical properties of the heat-sensitive substance;
- quantity of the heat-sensitive substance;
- lyophilization protocol;
- conditions of freeze-drying environment and/or equipment;
- projected storage duration;
- storage conditions (humidity, temperature, light exposure, etc.);
- reconstitution volume;
- reconstitution solvent; and/or
- intended use or application.
[0038] Once a container and membrane are selected, the container is filled with the heat-sensitive
substance in Filling Stage 420. The membrane is then introduced to the body of the
container as disclosed herein in Membrane Insertion Stage 430. Alternatively, when
the membrane is integrated into a cap, the cap is inserted onto the body of the filled
container.
[0039] During Lyophilization Stage 440, the container is held in a vertical position, by
self-standing or through the use of a tray or holder, such that the membrane is in
an upward-facing position. This membrane placement can allow for controlled and consistent
conduction of air and/or solvent vapor out of the container through the membrane.
The heat-sensitive substance then undergoes lyophilization. The membrane also prevents,
or at least reduces, entry of contaminants into the container during lyophilization.
The parameters of the lyophilization cycle or protocol and the equipment used can
be selected based on the identity of the heat-sensitive substance and its intended
downstream use. For example, if the heat-sensitive substance is a pharmacological
compound or biological material that will be administered to a patient, lyophilization
can be performed under appropriate regulatory conditions.
[0040] During Sealing/Packaging Stage 450, the lyophilized container is sealed and optionally
packaged. In some embodiments, the membrane provides a sealing mechanism for preventing,
or at least reducing, entry of liquids and/or contaminants during storage. In some
embodiments, Sealing/Packaging Stage 450 can include barcoding and tagging the container.
[0041] In Storage Stage 460, the lyophilized container is stored at conditions appropriate
for the freeze-dried material and its intended storage length.
[0042] Once a lyophilized container is selected for use, it is removed from storage and
reconstituted with an appropriate solvent in Reconstitution Stage 470. For example,
if the freeze-dried material is a drug that will subsequently be administered to a
patient, the material can be reconstituted with an appropriate volume of sterile saline
to reach the target therapeutic concentration for drug delivery. In some embodiments,
a syringe carrying a preferred solvent, can be used to pierce the membrane, disposed
in the lid or body of the container, and deliver the solvent to reconstitute the freeze-dried
material.
[0043] In Use/Application Stage 480, the reconstituted material is used for a particular
application. In some embodiments, during Use/Application Stage 480, the reconstituted
material is administered to a human or animal patient via infusion, injection, inhalation,
or oral administration.
[0044] Example implementations are described in the following clauses E1 to E15:
E1. A system comprising: an upright container comprising a body defined by an upper
portion, with an opening formed therein, and a lower portion; a removable cap sealably
attached to the upper portion of the body and configured to cover the opening; and
a membrane configured to transmit air or solvent vapor out of the upright container
while resisting liquid or contaminant passage into the upright container, the membrane
disposed above a fill line of the upright container.
E2. The system of clause E1, further comprising a membrane frame coupled to the perimeter
of the membrane.
E3. The system of clause E2, wherein the membrane frame attaches to the upper portion
of the body such that the membrane covers the opening of the upright container.
E4. The system of any one of clauses E2 or E3, wherein the membrane frame attaches
to the upper portion of the body via a lip and groove mechanism or threads.
E5. The system of clause E2, wherein the membrane frame is inserted into the upper
portion of the body.
E6. The system of clause E5, wherein the membrane frame is inserted into the upper
portion of the body via friction fit, a lip and groove mechanism, or threads.
E7. The system of clause E2, wherein the membrane frame is inserted into the cap of
the upright container.
E8. The system of clause E7, wherein the membrane frame is inserted into the cap via
friction fit, a lip and groove mechanism, or threads.
E9. The system of any one of clauses E1-E8, wherein the upright container is a lyophilization
vial.
E10. The system of any one of clauses E1-E8, wherein the upright container is a centrifuge
tube.
E11. The system of any one of clauses E1-E8, wherein the upright container is a blood
collection tube.
E12. The system of any one of clauses E1-E11, further comprising a heat-sensitive
substance.
E13. The system of clause E12, wherein the heat-sensitive substance is a biological
material.
E14. The system of clause E12, wherein the heat-sensitive substance is a pharmaceutical
formulation.
E15. The system of clause E12, wherein the heat-sensitive substance is a therapeutic
product.
[0045] While particular elements, embodiments and applications of the present invention
have been shown and described, it will be understood that the invention is not limited
thereto since modifications can be made by those skilled in the art without departing
from the scope of the present disclosure, particularly in light of the foregoing teachings.
1. A system comprising:
a container comprising a front wall attached to a back wall, the front wall having
an opening formed therein; and
a permeable membrane covering the opening in the front wall, the permeable membrane
configured to transmit air or solvent vapor out of the container while resisting liquid
or contaminant passage into the container,
wherein the container is configured to house a heat-sensitive substance during a freeze-drying
process.
2. The system of claim 1, wherein the container comprises a flexible, sealable material.
3. The system of claim 1 or 2, wherein the container comprises one or more of a medical
grade plastic, polypropylene, or high density polypropylene.
4. The system of any one of claims 1 to 3, wherein the heat-sensitive substance comprises
a biological material; and
optionally wherein the biological material is blood plasma.
5. The system of any one of claims 1 to 3, wherein the heat-sensitive substance comprises
a pharmaceutical formulation.
6. The system of any one of claims 1 to 3, wherein the heat-sensitive substance comprises
a therapeutic product.
7. The system of any preceding claim, further comprising a membrane frame coupled to
the front wall and a perimeter of the permeable membrane; and
optionally wherein the membrane frame is coupled to the front wall via a receiving
frame extending through the front wall.
8. The system of any preceding claim, wherein the back wall has a second opening formed
therein; and
optionally wherein a second permeable membrane covers the second opening in the back
wall.
9. The system of any preceding claim, wherein the container further comprises at least
one entry port configured to receive the heat-sensitive substance.
10. The system of any preceding claim, wherein the container further comprises at least
one entry port configured to receive a liquid configured to reconstitute the heat-sensitive
substance; and
optionally wherein the liquid comprises water or saline.
11. The system of any preceding claim, wherein the container further comprises at least
one application port configured to administer the heat-sensitive substance.
12. The system of any preceding claim, wherein the container is configured to hold about
250-270 mL of the heat-sensitive substance.
13. The system of any preceding claim, wherein the container further comprises a barcode
and an information tag; and
optionally wherein the barcode and information tag reflect one or more of an identification,
a storage condition, a reconstitution instruction, an administration instruction,
a blood plasma source, a blood type, or a date of collection.
14. The system of any preceding claim, further comprising an external foil containment
pouch configured to house the container.
15. The system of any preceding claim, wherein the container comprises a pouch.